Abstract: A well telemetry system supplies power to downhole sensor nodes employed for obtaining telemetry data in oil wells. The nodes are held in the cement that lines the well and surround the casing. At the surface, an AC power unit is connected to the casing and geological structure that surrounds the cement. Power to nodes is supplied using an AC resonant circuit that generates standing waves of electrical power on the casing. Power from the standing waves is delivered to the nodes which are located at antinodes of the standing wave. The nodes are held in cement that surround the casing, with one of their two electrodes connected to the casing and the other connected to the cement or to geological structure.

Abstract: A well telemetry system supplies power to downhole sensor nodes employed for obtaining telemetry data in oil wells. The nodes are held in the cement that lines the well and surround the casing. At the surface, an AC power unit is connected to the casing and geological structure that surrounds the cement. Power to nodes is supplied using an AC resonant circuit that generates standing waves of electrical power on the casing. Power from the standing waves is delivered to the nodes which are located at antinodes of the standing wave. The nodes are held in cement that surround the casing, with one of their two electrodes connected to the casing and the other connected to the cement or to geological structure.

Abstract: A discharge prevention system for a primary battery comprises an energy harvesting module that produces energy from an environment and a control circuit for applying electrical current to the primary battery from the energy harvesting module to prevent or reduce self-discharge. This system will prevent or reduce rapid self-discharge at high temperatures in lithium-based primary batteries, for example. It can significantly extend the operating lifetime of such batteries operating at high temperature, particularly in applications where battery power is used intermittently. Specifically, a very low current is supplied to the primary battery at high temperature, significantly extending its storage lifetime. In some cases, depending on the current characteristics of the battery, the energy associated with the bias current can be in the same order of magnitude as the energy that would be lost by self-discharge, but in many cases it is much lower.

Abstract: The disclosure is directed to a signal detection system. The system includes a receiver configured to receive data comprising noise and a signal having an amplitude lower than that of the noise received by the receiver. The system also includes a detection module configured to receive the data received by the receiver, define a region of interest of the data, compare a plurality of portions of the region of interest, and identify a portion of the region of interest that is more likely to contain the signal.